The present invention relates to a locking mechanism for releaseably mounting a row of filter elements in sealing engagement within a filter assembly or dust collector. The filter assembly for which this mechanism was particularly designed is of the back pulse self cleaning type similar in its general operation to that described in British Pat. No. 1,516,721 which, in turn, is quite similar in operation to the bag house filter assemblies which have been known for many years.
The more recent filter assemblies of this type comprise a large housing which is partitioned into a lower dirty air portion and an upper clean air portion. A plurality of rows of cylindrical pleated filter elements are removeably mounted in the lower portion of the housing such that the open upper end of the filter elements are in sealing engagement with the partition between the upper and lower portions of the housing. Apertures are provided in the partition in axial alignment with the open end of the secured filter element communicating the interiors of the filter elements with the upper clean air portion of the housing. Dust laden air is directed into the lower portion of the housing where it passes through the walls of the filter element, depositing its dust, and upwardly through the interior of the filter element into the clean air portion of the housing. The air is then exhausted through an air outlet whereupon the exiting clean air can be recirculated for ventilation, directed to the air intake of a large gas turbine or used for any number of purposes.
To prevent the individual filter elements in such an assembly from rapidly becoming overladen with dust particles, each filter element is repeatedly cleaned by back pulsing a jet of air downwardly through the interior of the filter element opposite to the direction of general air flow. This back pulsing forces the dust particles which have accumulated on the filter elements outwardly therefrom whereupon they fall to the bottom of the lower portion of the filter housing where they can be accumulated in a hopper for disposition. While such a cleaning technique vastly increases the useful life of the individual filter elements, they nevertheless require replacement which in such types of filter assemblies has heretofore been a quite dirty and time consuming operation.
The mechanisms heretofore employed for removably securing the filter elements in place, such as that taught by British Pat. No. 2,516,721, are not only quite awkward to operate requiring an excessive expenditure of time and effort in the replacement of the individual filter elements, but are constructed such that each mechanism secures only a single filter element in place. The large number and awkward positioning of the individual filter elements in such filter assemblies together with such difficult locking mechanisms make filter replacement an extremely dirty and unpleasant job. Further problems are created when toxic materials are being filtered, as the person changing the filter must position himself beneath the filter element he is removing in the path of falling toxic dust particles. In addition, these filter assemblies are often used on the air inlet end of large gas turbines which must be shut down during filter replacement. For these reasons, it would be highly desirable to provide a mechanism for releasably mounting these filter elements in such filter assemblies which would facilitate filter replacement and alleviate the aforesaid problems. The invention disclosed herein provides such a mechanism.